/*******************************************************************************************
 * Copyright (c) 2006-2009 Alex Robson, Rob Simmons, Craig Israel, and Rachel Twyford
 *
 * Use of this software in any form requires that you have both 
 * read and agreed to the following terms:
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the "Software"), 
 * to deal in the Software without restriction, including without limitation 
 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions: 
 *
 * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 * Redistributions in binary form must reproduce the above copyright notice, 
 * this list of conditions and the following disclaimer in the 
 * documentation and/or other materials provided with the distribution.
 * Neither the name of Nvigorate nor the names of its contributors may 
 * be used to endorse or promote products derived from this software without 
 * specific prior written permission. 
 *
 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 
 * DISCLAIMED. IN NO EVENT SHALL ANY CONTRIBUTOR BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * ****************************************************************************************/

using System;
using System.Collections.Generic;
using System.Linq;
using Nvigorate.Common;
using Nvigorate.Common.Reflection;
using Nvigorate.Extensions;
using Nvigorate.Relational.Mapping;
using Nvigorate.Relational.Mapping.Index;
using Nvigorate.Relational.Mapping.Interface;

namespace Nvigorate.Relational.Repository
{
    public class RelativeDecorator
    {
        public IBindingMap Map { get; set; }
        public object Instance { get; set; }
        public Dictionary<ITargetRelationship, Tuple<Type, Type, string>> RelativeKeys { get; set; }
        public static IRepositoryMapIndex Index { get; set; }
        public static Func<object, string> getString = o => o == null ? "" : o.ToString();

        public RelativeDecorator(IBindingMap map, object instance)
        {
            Map = map;
            Instance = instance;
            RelativeKeys = new Dictionary<ITargetRelationship, Tuple<Type, Type, string>>();
            var type = instance.GetType();
            Index.GetRelationshipsForType(type)
                .Where(r => r.RelativeType.Equals(type))
                .ForEach(r =>
                             {
                                 RelativeKeys.Add(r, GetKey(r));
                             });
        }

        public Tuple<Type, Type, string> GetKey(ITargetRelationship relationship)
        {
            var oneToMany = relationship as OneToManyRelationship;
            var manyToMany = relationship as ManyToManyRelationship;
            if(Instance.GetType().Equals(relationship.SubjectType))
            {
                return Tuple.Create(
                    relationship.SubjectType,
                    relationship.RelativeType,
                    oneToMany != null
                        ?
                            DelimitedBuilder.Construct(
                                oneToMany.Constraints.Select(c => getString(Reflector.Read(Instance, c.Key))), "|")
                        :
                            DelimitedBuilder.Construct(
                                manyToMany.Container.SubjectPairs.Select(p => getString(Reflector.Read(Instance, p.Target))), "|")
                    );
            }
            else
            {
                return Tuple.Create(
                    relationship.SubjectType,
                    relationship.RelativeType,
                    oneToMany != null
                        ?
                            DelimitedBuilder.Construct(
                                oneToMany.Constraints.Select(c => getString(Reflector.Read(Instance, c.Value))), "|")
                        :
                            DelimitedBuilder.Construct(
                                manyToMany.Container.RelativePairs.Select(p => getString(Reflector.Read(Instance, p.Target))), "|")
                    );
            }
        }
    }
}